Objective lens and method of manufacturing optical pickup apparatus

Abstract

An objective lens focusing light emitted from a light source onto an information surface of an optical disk, comprising: a first lens surface to be positioned on the light-source side; a second lens surface to be positioned on the optical-disc side; a first edge surface to be positioned on the light-source side, provided in an outer region of the first lens surface; and a second edge surface to be positioned on the optical-disc side, provided in an outer region of the second lens surface, a first optical axis of the first lens surface coinciding with a second optical axis of the second lens surface, the first optical axis and the second optical axis being orthogonal to the second edge surface.

1. A method of manufacturing an optical pickup apparatus including an objective lens focusing light emitted from a light source onto an information surface of an optical disc,
 the method comprising:
 assembling an optical block configured to cause light emitted from the light source to be incident on a first lens surface of an objective lens that includes the first lens surface on a light-source side, a second lens surface on an optical-disc side, a first edge surface provided on an outer region of the first lens surface, and a second edge surface provided in an outer region of the second lens surface, wherein a first optical axis of the first lens surface coincides with a second optical axis of the second lens surface, and wherein the first optical axis and the second optical axis are orthogonal to the second edge surface but not the first edge surface; 
 adjusting a tilt of the optical block so that an optical axis of light caused to be incident on the first lens surface of the objective lens from the optical block becomes orthogonal to a predetermined reference surface; 
 assembling an actuator being configured to drive the objective lens, and including a lens holder with a lens receiving surface, the lens holder configured to hold the objective lens such that the first edge surface of the objective lens is placed on the lens receiving surface; 
 mounting the actuator on the optical block having a tilt relative to the reference surface; and 
 adjusting a tilt of the actuator so that the second edge surface of the objective lens held in the lens holder becomes parallel to the reference surface. 
 
 
     
     
       2. The method of manufacturing an optical pickup apparatus of  claim 1 , wherein
 a plurality of the objective lenses are held in the lens holder, and wherein 
 the step of adjusting a tilt of the actuator includes:
 keeping a tilt of the actuator as a whole with a first jig, the tilt of the actuator as a whole having been adjusted such that the second edge surface of one objective lens out of the plurality of objective lenses becomes parallel to the reference surface; and 
 adjusting a tilt of each objective lens other than the one objective lens with a second jig, in sequence, such that the second edge surface of the each objective lens other than the one objective lens becomes parallel to the reference surface. 
 
 
     
     
       3. The method of manufacturing an optical pickup apparatus of  claim 2 , wherein
 the first edge surface of the each objective lens other than the one objective lens is shaped into a convex spherical seat, and wherein 
 the lens receiving surface of the lens holder, on which the first edge surface of the each objective lens other than the one objective lens is to be placed, is shaped into a concave spherical seat.